Astragalus - Medicinal Uses, Interactions, Side Effects, Dosage

Astragalus - Medicinal Uses, Interactions, Side Effects, Dosage
by Steve Mathew

Uses and Benefits:

In Chinese traditional medicine, the root of A. membranaceous is a popular and
potent tonic used for numerous specific indications, especially infections. It is thought
to improve depressed immunity, and therefore it has been recommended for the
treatment of AIDS and other viral diseases, and as an adjuvant in cancer therapy.
The herb is now advocated for a wide variety of illnesses, including the common cold,
influenza, respiratory insufficiency, diabetes, hypertension, liver disease, cardiac
ischemia, heart failure, vascular insufficiency, and nephritis.

Pharmacology:

The important constituents include numerous triterpene saponins, known as
astragalosides and related compounds such as soyasaponins. A number of
polysaccharides, such as astragalans I-IV, have been isolated. Important flavonoids
include quercetin and kaempferol; among its many other constituents are
isoflavonoids, sugars, amino acids, and linoleic acid. It is unclear which of the
numerous constituents are of therapeutic value. However, the polysaccharides and
saponins have been suggested to be the major agents.

The polysaccharide fractions of the root extract have been reported to have in vitro
effects that suggest an immune-enhancing capability. There is some evidence that
astragalus can potentiate the effect of interferon against viruses and can increase IgA
and IgM in nasal secretions in humans. Animal experiments have shown that extracts
of astragalus can restore the immune properties of cancer patient T-cells in vitro. A
more recent rat study does not confirm earlier reports that astragalus extract can
prevent myelosuppression by cyclophosphamide.

Clinical Trials:

Almost all of the clinical studies on astragalus are in Chinese medical books or
journals and are therefore not readily evaluated. In an open study on 1000 subjects,
8 it is alleged that a 2-month prophylactic course of the herb in a dosage of 8 g/day
in combination with interferon was correlated with a significant reduction in colds
compared to placebo or interferon alone. Benefits in humans for a wide variety of
chronic and serious disorders also have been reported. For example, it is asserted
that astragalus increases serum IgM, IgE, and cAMP; enhances left ventricular
function and cardiac output in patients with angina pectoris; improves hemorrhagic
indices in patients with systemic lupus erythematosus; increases survival in lung
cancer when combined with conventional therapy; improves leukopenia; improves
liver function in chronic viral hepatitis; and so on

However, none of these reports are evaluable, and the testing applied as well as the
observations made by investigators do not conform to standard methods used in
Western medicine. In general, these studies were uncontrolled or unblinded, and no
reliable clinical studies in support of these indications have been reported in the
English-language peer-reviewed literature. Thus, there is only very equivocal evidence
to support the numerous clinical claims that are made for astragalus, particularly as
an immune system restorative or as an immune modulator for use in the treatment
of cancer.

Adverse Effects:

Herbalists regard astragalus as very safe based on its reputation as a valued
traditional medication. It is unlikely that astragalus has any serious toxicity, although
there is a lack of reliable clinical data.

Side Effects and Interactions:

There are no recognized drug interactions.

Cautions:

Astragalus can be obtained in combination mixtures, in which other agents may have
a potential for toxicity.

Preparations & Doses:

Sliced astragalus root is often used to make teas, soups, or decoctions. The usual
daily dose varies from 2 to 30 g or more of the dried root; although large doses
appear to be safe, 8-15 g/day seems to be more reasonable. Some products
contain standardized extracts, packaged in unit doses. Capsules containing 150-500
mg are commonly marketed, to be taken as often as 8 or 9 times a day; tinctures
and fluid extracts are also available. In traditional Chinese medicine, it is usual to take
astragalus in combination with other herbs.

Summary Evaluation

A membranaceous is a popular Chinese herb that has long been used as a tonic.
Increasing claims suggest that it is of value as an immune restorative to fight viral
diseases, as a treatment for Lancer, and as a cure for other disorders. However, the
scientific evidence of clinical effectiveness is of unclear quality, and has not been
validated outside the Asian literature. Thus, actual benefits are not substantiated. The
fact that large doses can be taken with reported toxicity suggests that astragalus has
minimal pharmacologic potency.

About The Author

Steve Mathew is a writer, who writes many great articles on and
ayurvedic medicines for common ailments and diseases. Visit us for more
information on and .

Astragalus(Astragalus
membranaceous)rating:

The astragalus species that is
obtained from China is A.
membranaceous, also known as
Mongolian milk vetch, or by its
Chinese name, huang qi. It is quite
different from other species of
Astragalus, known as locoweeds,
which contain large amounts of
selenium and other potential toxins,
and from the Middle Eastern plant, A.
gummifer, which is the source of gum
tragacanth.

These statements have not been evaluated by the Food and Drug Administration (FDA). The content on
this website is for educational purposes only. Please consult with your physician before using natural
remedies and before making any drastic changes to your diet or exercise program.